Nanoscale Gate Field Effect Tube More Physical Characteristics And Model Research

At present, Semiconductor Industry is undergoing a huge revolution. Semiconductor devices are no longer restricted to the conventional planar structure. Instead, new three-dimensional structures are drawing more and more attention from both academic and industrial areas. The emergence and application of Double-Gate, Surrounding-Gare MOSFET, and FinFET enable the feature length continue to shrink. At the same time, the combination of new device structures and new materials are bringing more challenges to the process. As the result of the above two obvious reasons, quantum mechanical effects must be taken into account when we eatablish the model. This thesis focuses on the modeling of nanotransistor and the effects of the devices brought by physical parameters, and the new issues caused by device scaling down.First of all, we establish potential and threshold voltage models for Double/Surrounding-gate SB MOSFET. The Quantum mechanical effect and Schottky barrier lowering effect are included in the threshold voltage model. All of these will be helpful to the development of VSLI in the future. Due to the threshold voltage is one of the most important parameters of devices, we develop the double gate and surrounding gate device models, respectively. As the devices scale to nanometer scale, only a few dopants will result in a doping density to as high as1018cm-3, and unintentional impurities can be inevitable in the fabrication process. Further more, current-Voltage curve of the SB dopant segeragtion MOSFET is systematically analysed for performance improvement. Comparing with SB devices, SB DS devices exhibits a much better Ion/Ioff and subthreshold characteristics.Then we study the effect of I-V characteristic for a DG MOSFET caused by unintended dopants in channel with non-equilibrium Green’function. The subthreshold characteristics and Drain Induced Barrier Lowering (DIBL) effect are discussed from the quantum mechanical perspective. The device feature is impact by the number and position of dopants.This thesis focuses on the modeling and simulation of nanoscale dual gate device structures. Dual gate MOSFETs can greatly enhance the performance of trasistors, and are well recognized as the most promising candidate for next generation integrated circuit. Therefore, the modeling and simulation of the nanotransistor will be of great significance to Semiconductor Industry in the near future.